1. Field of the Invention
Suspended ceilings are used extensively in commercial and industrial buildings. In such ceilings, a metal grid framework of interconnected main beams and cross beams is hung from a structural ceiling by wires. The grid supports acoustical panels in rectangular openings formed in the grid.
This invention relates to the connectors used in the grid to join a pair of opposing cross beams and a main beam at grid intersections.
2. Prior Art
Suspended ceilings having metal beams interconnected into a grid that supports panels are well known. U.S. Pat. Nos. 5,839,246 and 6,178,712, for instance, incorporated herein by reference, show such ceilings.
The grid in such ceilings has, at each grid intersection, a pair of opposing cross beams and a main beam that form a connection.
The present invention relates to such a connection.
Each cross beam in such a connection has a connector at its end that is thrust, or stabbed-in, from opposing sides of the main beam, through a slot in the main beam. The connectors are all identical.
The connector that is first inserted into the slot is prevented from being withdrawn back out of the slot by the cantilevered latch in the connector, in the form of a pivoted flexible leaf spring. Such latch, which is integral with the connector base and formed therefrom by punching, is biased toward an open position. The latch, which is cantilevered at an angle from the base of the connector, flexes toward a closed position under the restraint of the side of the slot when the connector is stabbed through the slot to make the connection, but which then reflexes back to its biased rest position to prevent withdrawal of the connector back out of the slot.
Another connector on an opposing cross beam, identical to the first connector thrust through the slot, is then stabbed through the slot in the reduced space in the slot alongside the first. The latch on the connector contacts the side of the slot close to the latch pivot, and is flexed toward a closed position.
In inserting particularly the second connector into the slot, with a linear stab-in motion, substantial work and force are necessary to make the connection.
This resistance arises virtually immediately as the second connector into the slot enters the slot, and continues throughout the travel of the connector until it is seated in a locked position, as described below, with the first connector into the slot.
Both connectors interconnect when the second connector into the slot is fully inserted. Detents formed from the connector base, in the form of bulbs, that have a cam side and a locking side, and the ends of the connectors, flex and reflex to engage in what is sometimes referred to as a connector-to-connector lock, or “handshake” lock. Such a “handshake” connection between the connectors prevents the connectors from being pulled apart lineally out of the slot. The connectors are kept laterally and vertically together by the slot in the main beam.
In the seated locked position, the second connector is horizontally aligned with the first connector within the confines of the slot, so that the locking detents on the connectors are engaged and retained at the same level to form the connector-to-connector lock. Generally, the second connector must be either elevated or depressed as it passes into the slot to achieve such horizontal alignment. Hence, the profile of the leading edge of the connector is tapered to guide the connector during its travel though the main beam slot.
Such connectors are well known in the prior art and are disclosed, for instance, in the above referred to patents.
Numerous such connections must be made to create a ceiling grid.